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### Symblic matrices

Hi,

is it possible to define totally symbolic matrices. Something like

N,M = var('N,M')
a = matrix(SR, N, M)
b = matrix(SR, M, N)
c = a.dot(b)


So that c[i,j] = sum(a[i,k]*b[k,i],k,1,M) or do you really always need an non-symblic matrix size?

If you really always need a non-symblic matrix type, is it possible to define the symbolic variables automatically? Something like

a = matrix(SR, 2, 3)
print a[i,j]
output:
a_(i,j)


Thanks!

Manuel

 2 No.2 Revision niles 4419 ●23 ●68 ●128 http://nilesjohnson.net/

### Symblic Symbolic matrices

Hi,

is it possible to define totally symbolic matrices. Something like

N,M = var('N,M')
a = matrix(SR, N, M)
b = matrix(SR, M, N)
c = a.dot(b)


So that c[i,j] = sum(a[i,k]*b[k,i],k,1,M) or do you really always need an non-symblic matrix size?

If you really always need a non-symblic matrix type, is it possible to define the symbolic variables automatically? Something like

a = matrix(SR, 2, 3)
print a[i,j]
output:
a_(i,j)


Thanks!

Manuel